Image caption
The structure may mimic the way designers perceived sound-wave interference

Music could have been an inspiration for the design of Stonehenge, according to an American researcher.

Steven Waller's intriguing idea is that ancient Britons could have based the layout of the great monument, in part, on the way they perceived sound.

He has been able to show how two flutes played in a field can produce an auditory illusion that mimics in space the position of the henge's pillars.

Mr Waller presented the idea at the AAAS meeting in Vancouver, Canada.

He told the BBC: "My theory is that the ancient Britons, when they were hearing two pipers in a field, were experiencing sound wave interference patterns, where in certain locations as you walked around the pair of pipers, you would hear loud or quiet zones.

"If you could look at it from an overhead view, it would look like the spokes of a wheel. And, as you walk around the circle, every time you come to one of these sound-wave cancellation points, it feels like there is this massive invisible object in front of you.

"Put all this 'vision in your mind' together and it forms a Stonehenge-like structure."

Mr Waller is an expert in "archaeoacoustics", which examines the role sound might have played in ancient cultures.

'Supernatural explanations'

Image caption
The phenomenon of interference leads to amplified and silenced regions

He took these people into a field where two pipers were playing and afterwards asked them to draw diagrams of the soundscape they had experienced.

"These people were not told anything about interference patterns or Stonehenge; they were completely naive subjects," he recalled.

"And it was very interesting when they took the blindfolds off, and after having described the presence of large structures to then discover nothing was there in the field except these two flutes - they were flabbergasted."

Mr Waller said his ideas had been further strengthened by measurements he had made of the acoustic shadows actually cast by the Stonehenge megaliths. He found they accurately reproduced the interference pattern that would be generated by two flutes playing in the centre of the monument.

Mr Waller argued that the sounds' behaviour would have utterly captivated the ancients.

"People didn't even know that sound was propagated by pressure waves until a few centuries ago," he said.

"We know that sound was a great mystery to the ancients because there are many myths about echoes being a spirit that lives in the rock and which calls back, or that thunder was caused by large birds in the sky flapping their wings. They had supernatural explanations for all these sound phenomena."